This BSL-4 core provides the infrastructure to permit safe work to be performed on aerosol-infectious, potentially lethal agents. It consists of the mechanical safeguards of two high-containment laboratories, the provision of training in BSL-4 operations, and assistance in operations within the laboratories. Generally, the investigators will work within the laboratory, but about 20% of the effort will be devoted to challenge experiments using established animal models to test newly developed vaccines and therapeutics. Part of this core is located at Southwest Foundation for Biomedical Research (SF BR) in San Antonio, TX where 1200 ft(2) of BSL-4 laboratory space is available. The other component is scheduled for completion in June, 2003 and will provide 2000 ft(2) at the University of Texas Medical Branch, Galveston, TX. The SFBR facility has been in operation since March of 2000 and provides space for microbiological operations as well as housing for rodents and small non-human primates. UTMB will have 1000 ft(2) devoted primarily to animals and 1000 ft(2) mainly used to for microbiology. Both have access to a high intensity gamma irradiator allowing inactivation of samples for further analysis outside the BSL-4 laboratory. This core is essential for work on the hemorrhagic fever viruses and multidrug resistant highly pathogenic bacteria.